Convex Phillips Curve Explaining Openness and Inflation Nexus

摘要

We study the theoretical nexus between inflation and trade openness in the presence of a non-linear Phillips curve. Phillips curve explains the inverse relationship between unemployment and inflation; however, the open economy macroeconomic models usually propose that the slope of the trade-off should be related to the extent of trade openness. The role of openness as a check on inflation has recently attracted attention of many [1]. The parallelism between the recent globalization wave and the fall in inflation has led to a perception that the determinants of the slowdown in inflation were not only the domestic ones but could partly be due to increased trade openness. This study describes this relationship considering a non-linear Phillips curve. Using the conventional Phillips curve approximated by Cobb-Douglas model we confirm the earlier observations regarding the existence of a significant impact of openness on inflation. The interesting contribution of this study is not only to establish the trade-openness and inflation nexus but also to identify the relevant channels through which openness impacts inflation. Our model predicts that in the current scenario of increased openness a non-linear symmetric loss function may still prevail, but for the policy purposes it necessitates to consider domestic and foreign propensities to import and the exchange rate sensitivity to inflation. In addition, the integration of the international markets would result into an even more important role of exchange rate dynamics as a response to the rising international trade. We find that in the presence of a convex Phillips curve any upward variation in the foreigners’ propensity to import would place a downward pressure on domestic inflation, provided that the current and the lagged rate of unemployment are less than minimum unemployment rate. Our model, while assessing the short run dynamics, also suggests that increased openness results into a complex divide among different economies, due to their sizes and structures. Investigating such a relationship as an extension of this study for different economic groups could reveal further interesting facts.